PROFESSOR W. RAMSAY AND DR. S. YOUNG 
64 
Number of 
readings. 
Pressure reduced to 
0°, Mean. 
Volume, Mean. 
Pressure x Volume. 
Vapour density. 
mms. 
c.cs. 
2 
54-07 
175-25 
9476 
36-84 
1 
72-90 
129-95 
9473 
36-85 
2 
118-20 
79-92 
9447 
36-95 
1 
138-25 
67-80 
9374 
37-24 
2 
138-70 
67-40 
9348 
37-34 
2 
170-30 
55-00 
9355 
37-30 
2 
207-18 
44-90 
9302 
37-53 
2 
263-45 
35-02 
9227 
37-83 
2 
309-68 
29-60 
9166 
38-08 
2 
325-00 
28-05 
9116 
38-30 
Condensed 
330-00 
25-10 
— 
Vapour-pressure calculated, 330'48 mms. 
3. Constants at High Temperatures. 
For these experiments four different amounts of ether were employed. In the first 
case a large amount, A, was taken, and its weight calculated from its volume at 
known temperatures. During the early experiments a leakage took place, and, some 
ether being lost, the gauges had to be refilled. Measurements were again made to 
ascertain the weight of the remaining ether ; this portion is alluded to as A'. The 
third amount, B, was too small to be accurately determined in this way, and was 
estimated by comparison of the volumes occupied by the two quantities under similar 
conditions of temperature and pressure. The fourth quantity, C, was still smaller, 
and its weight was deduced from comparison of its volumes with those of B at the 
same temperatures and pressures. 
A. Results of experiments on large quantity of ether. Determination of iveight. 
The mean of the determinations of the specific gravity of ether at 0° by Ivopp, 
Pierre, Mendelejeff, and Perkin was taken. Their numbers were as follows :— 
Kopp (‘ Liebig’s Annalen der Cliemie und Pharmacie,’ vol. 64, p. 214) 0’73658 
Pierre (‘ Annales de Chimie et de Physique,’ vol. 15, p. 325) . . 073581 
Mendelejeff (‘ Liebig’s Annalen der Chemie und Pharmacie,’ vol. 
119, p. 9).0T3644 
Perkin (‘ Chem. Soc. Journ.,’ vol. 45, p. 474) . 07371 
„ „ „ . 07352 
Mean.07362 
Dr. Perkin’s results were from comparisons of ether and water at 15° and at 25°; 
the former is 072088, and the latter 070991. They were reduced to 0° by means of 
Kopp’s formula, with the above results. 
